Article ID: 106111
Article Last Modified on 1/8/2003
APPLIES TO
- Microsoft Visual Basic 3.0 Professional Edition
This article was previously published under Q106111
SYMPTOMS
When you create a Dynaset or Snapshot using the SQL PASSTHROUGH option with an ODBC database, the FindFirst, FindNext, FindLast, and FindPrevious methods give the error "Can't perform operation; it is illegal."
CAUSE
FindFirst, FindNext, FindLast, and FindPrevious work only on record sets opened by a query. Visual Basic version 3.0 doesn't use a query to open a record set when you use DB_SQLPASSTHROUGH, so these Find methods are not allowed, by design.
RESOLUTION
The SQL PASSTHROUGH option causes the query to be processed by an external database server, instead of by Visual Basic. Avoid using the SQL PASSTHROUGH option if you want to use the FindFirst, FindNext, FindLast, or FindPrevious methods with an ODBC database. Also, you can avoid the problem by creating a copy of the dynaset or snapshot. This will allow the Microsoft Access Engine to perform the FindFirst rather than allowing the ODBC server to do it. However, the the dynaset copy must not use the SQL PASSTHROUGH option. Here is an example:
Dim db as database
Dim ds as dynaset
Dim newds as dynaset
Set db = OpenDatabase("", 0, 0, "ODBC;DSN=texas")
Set ds = db.createdynaset("Select * from Authors", 64) ' SQL PASSTHROUGH
Set newds = ds.createdynaset() ' No SQL PASSTHROUGH
newds.FindFirst "" ' Now FindFirst works on newds
STATUS
This behavior is by design.
REFERENCE
Pages 58-60, Visual Basic Professional Edition, Version 3.0, "Professional Features Book 2."
MORE INFORMATION
Steps to Reproduce Behavior
The following code results in the "Can't perform operation; it is illegal" error:
Dim db As database
Set db = OpenDatabase("", 0, 0, "ODBC;DSN=texas")
Dim ds As Dynaset ' Creates a dynaset.
' The DB_SQLPASSTHROUGH option is 64:
Set ds = db.CreateDynaset("select * from authors", 64)
ds.FindFirst "" ' FindFirst causes error message.
Additional query words: 3.00
Keywords: kbprb KB106111
